Spring suspension for vehicles



Aug. 6, [1 940. A. F. HICKMAN SPRING SUSPENSION FOR VEHICLES Original Filed Feb. 27, 1934 :s' Sheets-Sheet 1 3 J N We 5 $21 5 n Q u l i1i QUE v T q it 11 H .7 g -5; & I 2

l g a g g; \NVENTOB W ATTORNEYS Aug. 6, 1940. HlCKMAN 2,210,241

' sramesusrhuszon .FOR vmucms Original Filod-Feb; 2'7. 1934 3 Sheets-Sheet 2 ATTORNEYS a a Aug. 6, 1940. A. FQHICKMAN SPRING SUSPENSION FbR VEHICLES Original Filed Feb. 27, 1934 3 Sheeis-Sheet 3 ll II M 6 ATTORNEYS a u Patented Aug. 6, .1940

PATENT OFFICE SPRING SUSPENSION roa VEHICLES Albert F. Hickman, Eden, N. Y., assignor to Hickman Pneumatic Seat 00. Inc., Eden, N. Y., a

corporation of New York Original application February 27, 1934, Serial No. 713,161. Divided and this application January 9, 1940, Serial No. 313,122

.24 Claims.

i (1) To resiliently oppose both up and down vehicle wheel movement by apurely geometric resilient resistance instead of by an arithmetic or a partially arithmetic and partially geometric resilient resistance, (2) to reduce vehicle side sway any desired amount down to and including zero side sway, and even beyond to any desired amount of negative side sway. (3) to eliminate wheel' tramp, (4) to considerably reduce the torsional forces to which the vehicle body is subjected, particularly astothe end of the body which is adjacent the axle being deflected, (5) to rapidly dampen out periodic vibration of the spring suspension even if,the shock absorbers should become more or less inoperative or even fractured, (6) to reduce the number of shock absorbers required on the vehicle and to reduce'the work imposed upon them, (7) to eliminate all frictional resistance except that incident to pivot bearings and shock absorbers, (8) to entirely eliminate the squeaks and lubrication inconvenience of the conventional leaf spring, (9) to definitely limit the stress to which the resilient elements may be subjected, (10) to'prevent the wheels from dragging the body down when said wheels move down beyond their normal range of movement, (11) to sion is below the component of the sprung weight I center of gravity of the companion axle, (14) to prevent the 'vehicle body from being subjected to lateral shocks as a consequence of lateral axle movement and to thereby also prevent tire scuff", (15) 'to prevent' any of the parts of a spring suspension pf this type from becoming locked in a past-dead-centerposition, (16), to

. enable the vehicle tolbe safely driven even if the resilient. members of the spring suspension become fractured, and (1'!) to provide means for enabling a considerable torsional deflection of a torsion member even though the overall length of the torsion member is relatively short. Numerous other objects of the invention and practical solutions thereof are described in detail in the herein patent specification wherein:

In the accompanying drawings:

Fig. 1 is'a diminutive,.top plan ofa passenger automobile chassis, provided with one form of my improved spring suspension.

Fig. 2 is a diminutive, vertical, longitudinal section thereof, taken on line 2-2, Fig. 1.

Fig. 3 is a fragmentary front-end elevation thereof showing the front axle and associated parts.

Figsui and 5 are fragmentary, longitudinal sections thereof, taken on correspondingly numbered lines of Fig. 3.

Fig. 6 is a fragmentary, vertical, longitudinal section through the rear end of the vehicle chassis, showing the rear axle and its associated parts. p v

Fig. '7 is a fragmentary, vertical, "transverse section-thereof, taken online 'I'-'|, Fig. 6.

' Fig. 8' is a fragmentary, vertical, transverse section thereof, similar to Fig. 7 but taken on a line indicated by 88 in Fig. 6 'and showing the parts in a different position from that of the other figures.

- Fig. 9 is a fragmentary, horizontal section thereof, taken on line 9-9, Fig. 6.

It is to be understood that similar characters of reference indicate like parts in the several figures of the drawings.

My invention may be embodied in various forms and in spring suspensions of different constfiictions, and the present, embodiments thereof are to be regarded merely as a few of the set-ups whichpar'ry out the invention in practice.

In the form of the invention shown-in Figs. 1-9, and in all the other forms of the invention, the main frame .of the vehicle chassis is constituted in the usual and well known manner of a pair of'longitudinal and substantially horizontal, side frame bars "and "I which are connected at their front and rear ends respectively by the front and rear cross bars ll and 3.

The entire vehicle cha'ssis,'together withits spring suspension, is constructed substantially symmetrically abouta vertical longitudinal medial plane,"and hence it is deemed sufflcient to confine the following description almost'entirely to the one (left) side ofthe vehicle, it being v front crank arm 4|.

metrical arrangement is to be found on the other (right) side of -thevehicle. Furthermore, the spring suspension at the rear end of the construction of Figs. 1-9 is-- somewhat simpler in construction than the front end, and will for that reason be described first.

Secured adjacent the rear end of the left, side, frame bar 30 is a pair of hangers 32 and 320. In the lower end of the forward hanger 32 (see Figs. 9, '7 and 6) is journalled a pivot pin 33| having a head and a nut similar in appearance to a bolt; Said pivot pin 33| is shown as connected through a universal joint 34 with a. torsion rod 33, the extreme forward end of the latter being shown as bent sharply upward to forni the torque arm 35, as shown in Figs. 4, 3, 2 and 1. The upper end of said torque arm is shownas provided with an adjusting screw 36, (or other suitable adjusting means) the inner end of which bears against a pad 31 which may, if desired, be constructed of resilient material such as rubber, and is suitably secured to the adjacent vertical longitudinal face of the companion frame bar 30. The purpose' of this adjustment screw 36 is to adjust the amount of torsional stress imposed upon its companion torsion rod 33.

It is to be understood that when such an adjustment is not desired, (if it be desired to render the device more fool-proof, for instance) the spring suspension may be produced with sufficiently restricted torsional and other tolerances, and said adjusting screw 36 then entirely eliminated. Likewise, the pad 31 may, if desired, be also eliminated, a resilient connection at this point being, as a matter of fact, of very small intrinsic worth due to the fact that only under very unusual circumstances will conditions be such as to allow the torque arm 35 to move away from the frame bar 30. It is likewise obvious that the universal joint 34 may also be eliminated if the vehicle set-up is such as to permit the two sections of the torsion rod 33 to be disposed in axial alignment with each other.

If desired, the intermediate portions of the torsion rod 33 may, as shown, be suitably supported on the frame bar 30 by'a pair of bearings 38 and 38 the latter being secured to said frame bars 30, 3|" in any suitable manner.

The rear portion or head of the universal joint 34 is suitably flanged and detachably connected by cap screws 40 with the inner end of a bifurcated, front crank arm 4|. This construction, in effect, rigidly connects the pivot pin 33| with said Itis obvious that such a rigid connection may be effected in numerous ways other than in the particular manner illustrated. When the vehicle is normally loaded and at rest, this front arm 4| projects outwardly and substantially horizontally from the torsion rod 33, as shown in Figs. '7, 6, 9, 1 and 2. In this position the outer end of said front crank arm 4| is resiliently urged downwardly by the resilient stress imposed upon it by the torsional stress of its companion torsion rod 33.

. As best shown in Fig. 9, the outer part of said bifurcated front crank arm 4| is connected on its outer rear side by an integral webbing 42 (or otherwise) with the outer part of a companion, bifurcated, rear crankarm 4). The inner end of this rear crank arm 4 I is provided with a pivot pin 43 which is pivoted in, the rear hanger 320.

aforedescribed. The axis of this pivot-pin 43 is coincident with the axis of the pivot pin 33| understood that a similar and substantially symthereby permitting the two crank arms 4| and 4| 0 (together with the integral webbing 42 which joins them) to swing in a vertical transverse plane about the common axis of said-pivot pin SM and of said pivot pin 43.

The outer ends of both of said crank arms "4| and 4H) are bifurcated and are provided with a pair of horizontal pivot pins 44 which are axially in line with each other. The central portion of each pivot pin 44 is pivoted in the normally lower end of a companion link 45, which latter, in the a normal or static, loaded position, of the vehicle spring suspension shown in Figs. 7, 6, 9, extends upwardlyvand inwardly from said pivot pin 44.

The upper ends of the two links 45 are split (see Fig. 7) and are clamped upon the opposite ends of a relatively long, horizontal, longitudinal, axle-pivot shaft 46. By reason of the fact that said links 45 are both clamped at their upper ends to said axle-pivot shaft 46, the term links is not strictly accurate, but has been here used to avoid excessively'clumsy phraseology and to more clearly distinguish said links" from the crank arms 4|, 4"].

Between said links 45 is disposed an upstanding Y shaped trunnion 41, the upper, bifurcated arms of which are journaled on said axle-pivot shaft 46 while its lower control part or head is suitably secured by welding or otherwise to a companion wheel spindle 48. The latter has a rear, driving wheel 50 journaled thereon in the usual and well known manner. This spindle 48 constitutes one of the outer ends of the rear or drive axle (or axle housing) When said drive axle 5| drops approximately to its lowermost position relatively to the vehicle frame, as shown in Fig. 8 there is a possibility (unless such a contingency be positively prevented) that the crank arms 4|, 4|0 and links 45 will be moved by inertia forces-past their deadcenter position, and become locked in this posi-v tion. To prevent any such occurrence a fiat, limiting spring 52 is secured to the central part of the trunnion 41 by means of cap screws 53 or otherwise, the outer portion of said limiting spring 52 being adapted to makecontact (see Fig. 8)

with the central, outer pbr'tion of the webbing tion, however, that, even ifthe parts move to or even beyond an absolute'deadcenter position, said parts are not likely to lock in this past-deadcenter position because the resilient force of the torsion rod 33 is always urging thepivot pins 44 downwardly, and this factor may, in actual practice, be quite safely relied upon to break any possible dead center locking.

When the axle 5| is forced upwardly relatively to the main frame from the position of Fig. It (or, vice versa, when the body under the influence of momentum, is forced downwardly relatively to said axle) the eflective resilient opposing force of the torsion rod 33 increases at a geometric and not at an arithmetic rate. In the particular case, the geometric rate is of the accelerated in;- crease type, in which increments of vertical movements of the axle are opposed by an accelerated rate of resilient resistance. This is primarily due to the progressive decrease in the eifective lever arm of the crank arms 4|, 4M, as they swing upwardly and inwardly about the rear section of the torsion rod 33 and the pivot pin 43 as an axis of rotation; This action "is also influenced by the varying angularity of the links 45 and the fact that increments of vertical displacement of the pivot pins 44 cause accelerated rates of increase in the angular displacement of the torsion rod "33. This latter is due to the fact that increments of vertical movement of said pivot pins 44 are not proportional to the accompanying increments of angular twist to which their companion torsion rod 33 is subjected.

This geometric action also occurs when the axle 5i moves downwardly a certain distance relatively to the frame bar from the normal posi tion of Fig. 7 to a position intermediate of the extreme position of Fig. 8. Throughout this particular movement, the geometric action is of the accelerated decrease type, i. e., as the axle passes through increments of downward movement, the

rate ofdecrease of thefi'esilient force tendingjto push said axle downward increases.

Thus, as the axle moves downwardly from the position of Fig. .7, the resilient force tending to push it downwardly decreases at anaccelerated rate. Finally, at a position intermediate of Figs. 7 and 8, this downward pressure on the axle 5i becomes equal to zero. Then, as said axle continues to move downwardly beyond this intermediate point, the torque arm is turned or rotated outwardly away from itspad 31, thereby relieving the torsion rod 33 of all torsional stress,

thereby maintaining at zero the value of the resilient force interposed betweenthe axle and the main frame. This condition continuesuntil the axle has moved downwardly to its lowermost position as shown in Fig. 8. During this last mentioned downward axlemovemenasaid axle, together with its wheels and other 'unsprung weight, rests with its entire weight upon the ground (assuming, of course, the latter to be within reach) and hence without any of said unsprung weight urging the main vehicle frame downward. This means that, as far as-vertical forces are concerned, said ,vehicle frame is, at this time, free to float" alongsolely. under the influence of gravity (plus whatever vertical momentum forces are present), this feature of the invention being of particular significance whenit is realized that the load carried by the vehicle is also, at this time, solely under the influence of gravity (plus whatever vertical momentum forces are present). The consequence is that, within this particular range of movement, the

load in the vehicle moves vertically up and down with the same acceleration and deceleration as the body and hence without changing the pressure between the load and body. Such a desirable result is quite different from that obtained from the conventional spring suspension in which the axle and the rest of the unsprung weight drags or jerks down the main frame whenever thestrain imposed on the main springs is tions to the resent invention when the same is to be applied to a front axle. In the case of the form of front axle 5' I I shown in Figs. 3, 4, 5. 1 and 2, for instance, a wheel spindle 4" having a wheel 5M journalled thereon is pivoted on a substantially vertical spindle pin II at each end of said front axle ii I: The two wheel spindles 4," at opposite ends of said axle are assumed to be cross connected for steering purposes in the usual. and well known manner. Extending horizontally inward from one of these spindles is a steering armjt connected by a universal joint 51 with the front end of the usual steering or drag link 58 (see Fig. 5 The rear end of the latter is connected, in the usual and well known manner,.by a universal joint 8| with the lower end of a manually actuated steering lever 6i.

It is important that the steering arm 56 be never moved relatively to theaxle 5 as a consequence of any sort of up and down axle movement. Any such deleterious movement has been absolutely prevented by the construction here illustrated. A radius rod 62 is connected at its front end by a universal joint "with the front axle 5H andis connected at its rear end by a universal joint 64 with the side frame bar 33 of the .main frame. This radius rod' 42 has its universal joint pivots 83 and i4 spaced apart the same distance as the spacing apart of the universal joint pivots 51 and I of the drag link". In addition to this, the disposition of the various pivot centers is such that all planes intersecting the pivots G3 and 64 of the radius rod 62 are parallel to all planes intersecting the pivots 51 and of the drag link 53.

A small amount of longitudinal clearance is I then provided at whereby the axle 5 with its trunnion 4H is free to slide a short distance in excess of one quarter of an inch, longitudinally -on the axle pivot shaft 46!, the latter being firmly clamped at its opposite ends in the upper split ends of the links 45L Because of this arrangement, as the axle 5H rises or fails, it is caused to move longitudinally about the pivot'64 as a center and to thereby prevent any turning of the spindle I about its vertical pivot 55 as the pivot 51 of said spindle swings about the drag link pivot 60. as a center. In actual practice the amount ofthis longitudinal movement of the front axle is so small, that both the radius rod 62 and clearance 65 maybe entirely eliminated without, any serious detrimental effect on the'steering of the vehicle.

There is one very important factorinvolved.

in any front axle set up, namely the permanence of the caster or the-angle in a vertical longitudinal' plane of the spindle pivots 55. His to be noted that, in the present invention. the caster irrespective of whether or not a radius rod 62 of the steering wheels remains absolutely'flxed,

. is used and-irrespective of whether the torsion' rod 33 becomes either deformed or even completely broken. This feature of fixed caster angle is also of some importance with respect to the back axle, where it ensures the permanency of the arcs through which the universal joints of the propeller shaft are caused to swing as the axle rises and falls. In the case of both front and rear axles, the construction whereby the caster angle is permanently maintained, irrespective of what may happen to the resilient portions of the spring suspension, also ensures that all torqueimposed upon the axles by the brakes is suitably taken care of without the need of any special torque rods for this purpose.

In the case of both the front and the rear axle spring suspensions, the linlrs 45, 4M incline downwardly and outwardly. This arrangement has two distinct advantages. One effect of this angular linkage arrangement is that it causes each end of the body of the vehicle to always tend to centralize itself relatively to the companion axle 5| or 5H asthe case maybe. This centralizing tendency is caused by the efl'ect of gravity, which may be considered a resilient, downwardlyacting force acting between the body and the roadbed and operating in a manner identical in its effects to a metal spring connecting said body and the roadbed. It is to be distinctly understood that this force tending to centralize each end of the body is of a resilient nature. Because of this fact the body of the vehicle is not subjected to directly connected lateral forces as a consequence of a lateral axle movement. Such a lateral axle movement occurs, for instance, when one end only of the axle is raised or depressed and thereby causes horizontal, lateralmovement components in all parts of the axle except at-its momentary axis of rotation in those particular cases where said axis lies within the spring suspension, all mcvernentsof the axle which are lateral with respect to the vehicle as a whole are transmitted directly to the body. Because of the relatively large inertia of the latter, no appreciable lateral body movement actually occurs when such a conventional vehicle is travelling at high speeds and one end of the axle moves up or down. What does occur is that. said body is subjected to a sharp lateral rap of considerable force everytime the axle moves in any manner other than translationally. This not only seriously impairs the riding qualities of the vehicle but also subjects the body to a succession of forces which in a short period of time loosen all the body bolts and other such fastenings and cause the whole body to rattle.

Another important advantage obtained by the angular arrangement of the links 45, 45| is that it absolutely eliminates wheel tramp. This latter may be broadly defined as a periodic vibration of either axle in a vertical transverse plane, the definition being usually limited to a rotary movement aboutan axis of rotation located at some point in the axle. In general it may be said that, if one wheel is lifted, and if this movement causes a downward thrust on the opposite wheel, then wheel tramp results. Suchwheel tramp is prevented in the present invention by ensuring that the downward thrust of the axle pivot 46 or I, as the case may be, lies approximately in a plane intersecting the contact of the tire with the road. When such a condition obtains, a vertical upward thrust against one wheel is opposed by a directly opposite force passing through the axle pivot 46 or 46l and hence no downward thrust is imposed upon the opposite wheel as occurs in the conventional spring suspension.

Another very important advantage ofthe present invention is that all forces tending to twist the frame have been very markedly reduced as compared with conventional spring suspensions.

hangers 32, 320 (MI, 32"!) are subjected to a force intersecting the axis. of. the pivot pin 43 duced.

(and adjacent short end of the companion torsion rod 33). Such a force constitutes a torque force imposed upon the adjacent end of the vehicle frame, and this, all by itself, would, of course, cause frame twist. It is to be noted, however,- that, at this time, the companion torsion rod 33 is under increased stress by reason of the wheel thrust in question and hence the torque arm 35 is subjected to an increased force which also constitutes a torque force upon the vehicle frame. It is to be noted that this increased force which is imposed upon said torque arm 35 is located at one end of the vehicle while the torque force at the pivot pin 43 is at the other end of the vehicle. Furthermore, the forces are not7greatly difierent in intensity or direction. The result of this condition of affairs is that both ends of the vehicle are subjected to torque forces which do not differ from each other to any marked degree in either direction or intensity, and hence frame twist is very considerably re- In other words, when a certain wheel of the vehicle is forced upward, instead of twisting the one end of the vehicle frame as in the conventional spring suspension the present invention provides that the entire one side of the vehicle will be lifted a minute distance, thereby increasing the inertia resistance of the sprung weight to the resilient forces caused by the wheel movement, and very markedly decreasing frame twist and its concomitant twisting and rocking of the body and resulting loosening of the various body fittings,

As to this matter of frame twist, it is to be noted that satisfactory results. can only be obtained if the dead end of the torsion rod extends toward the opposite end of the vehicle and is positioned beyond the center of gravity of the car. If this condition does not obtain, then both ends of the torsion rod cause torque forces which act in the same general direction and upon the same end of the vehicle and hence cause frame twist. If, as in the present invention, the dead end of the torsion rod is situated beyond the center of gravity of the sprung weight (body) then the forces are acting upon opposite ends of the vehicle and frame twist is reduced.

It is also to be noted in the present invention that the means whereby resilience is effected does not involve any frictional resistance such as occurs in the case of a conventional leaf spring, and hence is free and non-energy absorbing in its action. Also, having no frictional resistance (except bearings which afford no particularly diflicult. lubrication problems) it does not vary because of change of frictional resistance as in the case of the conventional leaf spring.

No shock absorbers are illustrated as used in conjunction with the spring suspension. However, Git is desirable to employ shock absorbers in connection with this suspension. .Nevertheless the riding qualities of a vehicle equipped with the present invention are not seriously reduced even if the shock absorbers become inoperative or are left off altogether. This is in sharp contrast to the ordinary individually sprung wheel suspension using helical springs, in which case the vehicle receives a terrific wracking and pounding if the shock absorbers become even partially inoperative. In the present inventiom-it. has been found by definite test, that the periodic vibrations of the spring suspension are very rapidly damped out, even in the total absence of shock absorbers. As an example of right or left, creates a lateral force which tends how marked the dampening action is, a series of tests were runon three types of spring suspension in which the load and displacement were the same and also the maximum metal stress in ,the respective resilient members. It was found that a helical spring, under these circumstances, would come to rest after 800 vibrations, the leaf spring after 20 vibrations, and the present invention after vibrations. Why the leaf spring should be so superior to the helical spring is easy to understand because of the relatively high friction in a leaf spring even when well 'lubricated. The significant fact is that inapplicants spring suspension, there is no such leaf spring friction and yet its performance is four times as good as the leaf spring set up, despite the fact that the frictional resistance of the present invention is not materially different from that of the helical spring, individually sprung wheel set up.

In the present invention, side sway of the vehicle frame can be reduced to any desired extent including zero side sway and even negative side sway. To'deal rationally with this question it is highly .desirable that we first mathematically split the center of gravity of the car into two components, each component lying in the intersection of. a verticle, longitudinal, medial plane with vertical, transverse planes passing through the axes of the companion pair of wheels. Each component of the center of gravity is then the mass which, when the vehicle is steered to the to tip its companion end of the vehicle in a lateral direction relatively to the; companion. .The reason why it is desirable to deal with a center-of-gravity component over each axle individually is because the component over the a line ii, there results a zero side sway of the frame relatively to the axle when the vehicle is turned to the right or left as, for instance, when rounding a corner. This is because said line d intersects the axis of the axle pivot 46!.

This is believed by the inventor to be a correct statement, but it is admitted that no specific tests have been made to ascertain exactly where the center of gravity must be to obtain zero side sway.

However, assuming this relationship, as stated,

to be correct, then it follows that if the centerof-gravity component isabove the line it the resulting side sway will be positive as in the conventional spring suspension.

If, on the other hand, the center-of-gravity component is situated below the line 6, as for instance, on line e, then the side sway isnegative.

Obviously the amount of such negative side sway is proportional to the distance between he lines it and e. One important feature of negative side sway is that, when rounding a corner, the

, center of gravity is shifted toward the inside of of the person or goods in the vehicle to move sidewise under the influence of centrifugal force is lessened. This is because the supporting surface is tilted when the side sway occurs and hence one component of the side sway force is directed perpendicularly downward against said supporting'surface. Negative side sway has the further advantage of being much superior as to its psychological reaction on the persons riding in the vehicle as compared with zero or positive side sway, not .only because of the decrease inv the force tending to move the persons sidewise in their seats, but also because there is a natural tendency for a person to lean inward (or bank) on a curve. This psychological ef ect is probably chiefly due to the instinctive feeling of greater safety which is obtained when the center of gravity is-shifted toward the inside of the curve along which the person is moving.

It is obvious that the amount of side sway varies with the position 'of the axle pivots relaaxle are approximately in the extreme position of Fig. 8'. This is due to the fact that, when the parts are approximately in this position, any outward centrifugal movement of the inner part of the vehicle frame, tends to cause the pivots 43, 4 4

and 46 to all lie in one straight line, and such a "dead center" tendency is resisted by forces which rapidlyapproach infinity as said pivots approach a straight line relationship. It should be borne in mind, however, that any such condition as that shown in Fig. 8 would be exceeding rare in actual practice, particularly when the vehicle-is equipped with shock absorbers whose chief function is to restrain upward movements of the body relatively to the axle.

It hasalso been found in the present invention from actual practice and from analysis based on said practice that side sway has been. rendered mathematically more negative in amount-by reason of the angularity ofthe links 45 which normally slope down and out from the axle pivots I. Because of this angularity,when the body,

shifts laterally in rounding a curve, the outer part 'of the body is elevated and the inner part allowed, to fall, relatively to the axles. Such a tilting is equivalent in-its effect to lowering the' center of gravity of the body or elevating the axle pivots I, either of these changes rendering side sway morenegative.

From the foregoing it will be seen that the present invention provides a suspension which is particularly applicable to the use of torsion rods as the spring means for supporting the vehicle, although the invention is not limited to the use of such rods. It will further be seen that by providing bearing surfaces for'the crank arms and links which are extended lengthwise of the vehicle, these parts in and of themselves resist all brake and driving torque which is imposed upon the vehicle. It will further be seen thatby the inclination of the shackles or links inwardly a upwardly from the crank arms to the axle pi ot the axles are rendered self-centering and at the same time the axle is capable of being 60 the frame and axle of a vehicle and comprising:

moved sidewise so as to provide lateral cushioning. I claim as my invention:

1. A vehicle spring suspension for connecting the frame and axle of a vehicle and comprising: a crank arm pivoted longitudinally on said frame; said crank am having a pivot at its outer part; an axle pivot connected to said axle; means pivoted at its upper end on said axle pivot and at its lower end on said crank arm' pivot, said means extending upwardly and inwardly from said crank arm pivot when said crank arm is in a horizontal position; and resilient means to resist rotation of said crank arm.

2. A vehicle spring suspension for connecting the frame and axle of a vehicle and comprising: a crank arm pivoted longitudinally on said frame; said crank arm having a pivot at its outer part; an axle pivot connected to said axle; means pivoted at its upper endton said axle pivot and at its lower end on said crank arm pivot, said means extending ,upwardly and inwardly from said crank arm pivot when said crank arm is in a horizontal postion; and a torsion rod connected at one end to said frame and extending longitudinally of said frame and connected at its opposite end to said crank arm to resist rotation of said crank 'arm.

3. A vehicle spring suspension for connecting the frame-and axle of avehicle and comprising: a crank arm pivoted longitudinally on said frame; said crank arm having a pivot at its outer part; an axle pivot connected to said axle; means pivoted at its upper end on said axle pivot and at its lower end on said crank arm pivot, said meansextending upwardly and inwardly from said crank arm pivot when said crank arm is in a horizontal position; and the distance between the inner and outer crank arm pivot centers never exceeding two and one-half times the distance between the pivot centers of said axle pivot and said outer crank arm pivot; and resilient mean to resist rotation of said crank arm.

4. A vehicle spring suspensin for connecting the frame and axle of a vehicle and comprising: a crank arm pivoted longitudinally on said frame, said crank arm having a pivot at its outer part; an axle pivot connected to said axle; means pivoted at its upper end on said axle pivot and at its lower end on said crank arm pivot, said means extending upwardly and inwardly from said crank arm pivot when said crank arm is in a horizontal position; and resilient means toresist rotation of said crank arm; said elements being so arranged that the line of force derived from said axle and directed against the said pivot at the outer part of said crank arm is able to pass through the axis of said crank arm.-

5., A vehicle spring suspension for connecting a crank arm pivoted longitudinally on said frame, said crank arm having a pivot at its outer part; an axle pivot connected to said axle;

means pivoted atits upper end on said axle pivot and at its lower end on said crank arm pivot, said means extending upwardly and inwardly from said crank arm pivot when said crank-arm is in a horizontal position; and a torsion rod normally connected at one end to said frame and extending longitudinally of said frame and connected at its opposite end to resist rotation of .said crank arm; said elements being so arranged that the line of force derived from said axle and direct d against the said P vot at the outer part a crank arm pivoted longitudinally on said frame;

a pivot at the outer part of said crank arm; an axle pivot on said axle; means connecting said axle pivot with said crank arm pivot; the pivot mounting for said crank arm and said crank arm pivot and axle pivot each including means maintaining the axes thereof parallel with the axis of said pivot mounting for said crank'arm thereby to resist all brake and drive torque reactions in all positions of said axle, crank arm and connecting means; and means resiliently resisting vertical axle movement relative to said frame.

7. A vehicle spring suspension for connecting the frame and axle of a vehicle and comprising: a crank arm pivoted longitudinally on said frame; a pivot at the outer part of said crank arm; an axle pivot on said axle; means connecting said axle pivot with said crank arm' pivot; the pivot mounting for said crank arm and said crank arm pivot and axle pivot each including means maintaining the axes thereof parallel with the axis of said pivot mounting for said crank arm thereby to resist all brake and drive torque reactions in all positions of said axle, crank arm and connecting means; and means resiliently resisting vertical axle movement relative to said frame; said elements being so arranged that the line of force derived from said axle and directed against the said pivot at the outer-part of said crank arm is able to pass through the axis of said crank arm.

8. A vehicle spring suspension for connecting the frame and axle of a vehicle and comprising: a crank arm pivoted longitudinally on said frame; a pivot at the outer part of said crank arm; an axle pivot on said axle; means connecting said axle pivot with said crank arm pivot; the pivot mounting for said crank arm and said crank arm pivot and axle pivot each including means main taining the axes thereof parallel with the axis of said pivot mounting for said crank arm thereby to resist all brake and drive torque reactions in all positions of said axle, crank arm and conheating means; and means connected to and resiliently.resisting rotation of said crank arm.

9. A vehicle spring suspension for connecting the frame-and axle of a vehicle and comprising: a crank arm pivoted longitudinally. on said frame; a pivot at the outer part of said crank arm; an axle pivot on said axle; means connectingsaid axle pivot with said crank arm pivot; the pivot mounting for said crank arm'and said crank arm pivot and axle pivot each including means maintaining the axes thereof parallel with the axis of said pivot mounting for said crank arm thereby to resist all brake and drive torque reactions in all positions of said axle, crank arm and connecting means; and a torsion rod connected at one end to said frame and extending longitudinally of said frame and connected at its opposite end to said crank arm to resist rotation of said crank arm.

10. A vehicle spring suspension for connecting the frame and axle of a vehicle and comprising: a crank arm pivoted longitudinally on said frame; a pivot at the outer part of said crank arm; an axle pivot on said axle; means connecting said axle pivot with said crank arm pivot; the pivot mounting-for said crank arm and said crank arm pivot and axle pivot each including means maintaining the axes thereof parallel with the axis of said pivot mounting forsaid crank arm therebyto resist all brake and drive torque reactions in all positions of said axle, crank arm and connecting means; and means resiliently resisting rotation of saidcrank arm; said elements being so arranged that the line of force between said axle pivot and said crank arm pivot in the normal position of said elements extendsupwardly and mounting for said crank arm and said crank arm pivot and axle pivot each including means maintaining the axes thereof parallel with the axis of said pivot mounting for said crank arm thereby to resist all brake and drive torque reactions in all positions of said axle, crank arm and connecting means; and means resiliently resisting rotation of said crank arm; said elements being so arranged that the line of force derived from said axle and directed againstthe said pivot at the outer part of said crank arm is able to'pass through the axis of said crank arm.

12. A vehicle spring suspension for connecting the frame and axle of a vehicle and comprising:

a crankarm pivoted longitudinally on said frame;

a pivot at the outer part of said crank arm; an axle pivot on said axle; means connecting said axle pivot with said crank arm pivot; the pivot mounting for said crank arm and said crank arm pivot and axle pivot each including means maintaining the axes thereof parallel with the axis of said pivot mounting for said crank armthereby to resist all brake and drive torque reactions in all positions of said axle, crank arm and connecting means; and means resiliently resisting rotation of said crank armpsaid elements being so arranged that the line of force derived. from said axle and directed against the said pivot at the outer part of said crank arm is able to pass through the axis of said crank arm; and said means connecting said axle pivot with said crank arm pivot extending upwardly and inwardly from said crank arm pivot to said axle pivot in the normal position of said elements.

'13. A vehicle spring'suspension for connecting the frame and axle of a vehicle and comprising: a crank arm pivoted longitudinally on said frame; a pivot at the outer part of said crank arm; an axle pivot on-said axle; means connecting said axle pivot with said,crank arm pivot; each of said pivotal connections including hearing means and each of said bearing means being extended longitudinally of said frame to resist substantially all brake and drive torque reactions in all positions of said axle; and means resiliently resisting vertical axle movement relative to said frame. I

14. A vehicle spring suspension for connecting the frame and axle of a vehicle and comprising: a crank arm pivoted longitudinally on said frame; a pivot at the outer part of said crank arm; an axle pivot on said axle; means connecting said axle pivot with said crank arm pivot; each of said pivotal connections including bearing means and each of said bearing means being said elements being so arranged that the line of force derived from said axle and directed against the said pivot at the outer part of said crank arm .is able to pass through the axis of said crank arm.

15. A vehicle spring suspension for connecting the frame and axle of a vehicle and comprising: a crank arm pivoted longitudinally on said frame; a pivot at the outer part ofsaid crank arm; an axle pivot on said axle; means connecting said axle pivot with said crank arm pivot;

each of said pivotal connections including bearing means and each-of said bearing means being extended longitudinally of said frame to resist substantially all brake and drive torque reactions in all positions of said axle; and means for resiliently restraining rotation of said crank arm;

said elements being so arranged that the line of force between said axle pivot and said crank arm pivot in the normal position of said elements extends upwardly and inwardly from said crank arm pivot through said axle pivot.

16. A vehicle spring suspension for connecting the frame and axle of a. vehicle and comprising:

a crank arm pivoted longitudinally on said frame; a pivot at the outer part of saidv crank arm; an axle pivot on said axle; means connecting said axle pivot with said crank arm pivot; each of said pivotal connection including bearing means and each of said bearing means being extended longitudinally of said frame to resist substantially all brake and drive torque reactions in all positions of said ,axle; and a torsion rod connected at one end .to said frame and extending longitudinally of said frame and connected 'at its opposite end,to said crank arm to resist rotation of said crank arm.

17. A vehicle spring'suspension for connecting the frame and. axle of a vehicle and comprising: a crank arm pivoted longitudinally on said frame; a plurality of crank arm pivots at the outer part and at opposite sides of'said-crank arm; an axle pivot having a plurality of bearing surfaces spaced longitudinally of said frame; a plurality of links each connecting one of said bearing surfaces with the corresponding pivot atthe outer end of said crank arm and said links and the pivotal connections thereof with said pivots being spaced longitudinallyof said frame to resist substantially all brake and drive torque reactions; and resilient means to resist vertical movement of said axlerelative to said frame.

18. A vehicle spring suspension for connecting the frame and axle of a vehicle and comprising:

a crank arm pivoted longitudinally on said frame; a plurality of crank arm pivots at the outer part and at opposite sides of said crank arm; an axle axle and directed against the said pivots at the outer part of said crank arm is able to pass through the axis of said crank arm.

19. A vehicle spring suspension for connecting the frame and axle of a vehicle and comprising:

a crank arm pivoted longitudinally on said frame;

and at opposite sides of said crank arm; an axle pivot having a plurality of bearing surfaces spaced longitudinally of said frame; a plurality of links each connecting one of said bearing surfaces with the corresponding pivot at the outer end of said crank arm and said links and the pivotal connections thereof with said pivots being spaced longitudinally of said frame to resist substantially all brake'and drive torque reactions; and resilient means for resisting rotation of said crank arms; said links connecting said axle pivot and the pivots at the outer part of said crank arm extending upwardly and inwardly from said vpivots at the outer part of'said crank arm to said axle pivot in the horizontal position of said crank arm.

20. A vehicle spring suspension for connecting the frame and axle of a vehicle and comprising: a crank arm pivoted longitudinally on said frame'jja plurality of crank arm pivots at the outer part and at opposite sides of said crank arm; an axle pivot having a plurality of bearing surfaces spaced longitudinally of said frame; a plurality of links each connecting one of said bearing surfaces with the corresponding pivot at the outer end of said crank arm and said links and the pivotal connections thereof with said pivots being spaced longitudinally of said frame to resist substantially all brake and drive torque reactions; and a torsion rod connected at one end to said frame and extending longitudinally of said frame and connected at its opposite end to resist rotation of said crank arm.

21. A vehicle spring suspension for connecting the frame and axle of a vehicle and comprising: a crank arm pivoted longitudinally of the frame; means connecting said axle and crank arm and including a pivot at the outer part of said crank arm; an axle pivot on said axle; and a shackle connecting said axle pivot with said crank arm pivot, each of said pivotal connections including bearing means and each of said bearing means the frame and axle of a vehicle and comprising:

a crank arm pivoted longitudinally of the frame;

means connecting said axle and crank arm and including a pivot at the outer part of said crank arm; an axle pivot on said axle, and a shackle connecting said axle pivot with said crank arm pivot, each of said pivotal connections including bearing means and each of said bearing means frame without causing said axle to rotate relative to said frame; and resilient means to resist vertical movement of said axle relative to said frame.

23. A vehicle spring suspension for connecting the frame and axle of a vehicle and comprising:

a crank arm pivoted longitudinally of the frame; means connecting said axle and crank arm and including a pivot at the outer, part of said crank arm; an axle pivot on said axle, and a shackle connecting said axle pivot with said crank arm pivot, each of said pivotal connections including bearing means and each of said bearing means being extended longitudinally of said frame to resist substantially all brake and :drive torque reactions; means included in said connecting' means and permitting at least one-fourth inch of movement of said axle longitudinally of said frame without causing said axle to rotate relative to said frame; and resilient means resisting rotation of said crank arm; said elements being so arranged that the line of force derived from said axle and directed against the said pivot at the outer part of said crank arm is able,

- and pair of shackles being arranged inplanes extending longitudinally of said frame to resist substantially all'brake and drive'torque reactions and longitudinal thrust from said axle to said frame; and resilient means to resist vertical movement of said axle relative to said frame.

- ALBERT F. HICKMAN. 

